Apparatus for manufacturing fine metallic filaments

ABSTRACT

Apparatus for producing fine metallic filaments which comprises: SUPPLY MEANS FOR SUPPLYING A DRAWN COMPOSITE WIRE COMPRISING A BUNDLE OF A PLURALITY OF METALLIC FILAMENTS SURROUNDED BY AN OUTER METAL TUBE; CUTTING MEANS COMPRISING CUTTING BITES ARRANGED SYMMETRICALLY WITH RESPECT TO THE COMPOSITE WIRE IN THE CUTTING MEANS FOR CUTTING AND REMOVING MOST OF THE OUTER METAL TUBE OF THE COMPOSITE WIRE ON OPPOSITE SIDES OF THE METAL TUBE; ROLLING MEANS COMPRISING OPPOSITELY DISPOSED ROLLS FOR PRESSING THE UNCUT SIDES OF THE COMPOSITE WIRE AND TO CAUSE THE COMPOSITE WIRE TO BE COMPRESSED AND SPREAD OUTWARDLY IN A DIRECTION PERPENDICULAR TO THE CUT SIDES OF THE METAL TUBE AND FOR CAUSING THE METAL TUBE TO DIVIDE AT THE CUT SURFACE; AND PICKUP MEANS FOR TAKING UP THE DIVIDED PARTS OF THE METAL TUBE AND THE METALLIC FILAMENTS.

United States Patent 1191 Tada et al.

[4 Oct. 1,1974

[ APPARATUS FOR MANUFACTURING FINE METALLIC FILAMENTS [75] Inventors:Yoshiyuki Tada; Hideo Ogita;

Takeshi Yoda, all of Itami, Japan [73] Assignee: Sumitomo ElectricIndustries, Ltd.,

Osaka, Japan [22] Filed: Oct. 16, 1973 [21] Appl. No.: 406,987

Related US. Application Data [62] Division of Ser. No. 254,124, May 17,1972, Pat. No.

[30] Foreign Application Priority Data May 17, 1971 Japan 46-33080 [52]US. Cl. 29/200 B, 29/200 D, 29/413,

[51] Int. Cl B23p 19/00, B23p 19/04 [58] Field of Search 29/200 D, 200B, 413, 419

[56] References Cited UNITED STATES PATENTS 3,254,396 6/1966 Mushey29/413 3,337,944 8/1967 Morris 29/413 Primary Examiner-Thomas H. EagerAttorney, Agent, or FirmSughrue, Rothwell, Mion, Zinn & Macpeak 5 7ABSTRACT Apparatus for producing fine metallic filaments whichcomprises:

supply means for supplying a drawn composite wire comprising a bundle ofa plurality of metallic filaments surrounded by an outer metal tube;cutting means comprising cutting bites arranged symmetrically withrespect to the composite wire in the cutting means for cutting andremoving most of the outer metal tube of the composite wire on oppositesides of the metal tube; rolling means comprising oppositely disposedrolls for pressing the uncut sides of the composite wire and to causethe composite wire to be compressed and spread outwardly in a directionperpendicular to the cut sides of the metal tube and for causing themetal tube to divide at the cut surface; and pickup means for taking upthe divided parts of the metal tube and the metallic filaments.

4 Claims, 6 Drawing Figures PAIEmmnm H974 FIG. 3

FIG. 2

FIG. I

FIG. 4

FIG 5 APPARATUS FOR MANUFACTURING FINE METALLIC FILAMENTS This is adivision of U.S. Pat. No. 3,785,036 Tada et al., issued Jan. 15, l974from an application filed May 17, 1972, Ser. No. 254,124.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to apparatus for producing a yarn of fine metallic filaments atlow cost, and especially to a novel apparatus of producing a yarn offine metallic filaments by bundle drawing wherein the outer metal tubeof a composite wire is mechanically separated from core filamentspresent inside the outer tube.

2. Description of the Prior Art In recent years, fine metallic wiresabout 0.150 to 0.005 mm in diameter made of carbon steel, alloy steel,stainless steel, etc. or yarns or slivers thereof have foundapplications as tire cords, metallic fibers for blending purposes, orfine metallic fibers for filters, etc. Generally, in the single wiredrawing process using a die, the production of fine metallic, filamentsmust be performed by the repetition of heat-treatments and drawings, andthe productivity is low. This leads to an extreme increase in the costof production. In an attempt to overcome these disadvantages, the bundledrawing process was devised, and has been utilized to some extent.

The conventional bundle drawing method comprises first coating thesurfaces of material wires with a separator such as a metal oxide,graphite or an oil, which prevents the metallic bonding of the wiresduring the drawing and heat-treatment operations, or with a differentmetal by, for example, plating; inserting a bundle of a plurality ofsuch material wires in a tube of a different metal, or covering thisbundle of wires with a metallic tape at its outer circumference, andwelding the seam portion thereby to form a composite wire; subjectingthe composite wire to a diameter reduction treatment by drawing, andheat-treatment, etc. until the diameter of each filament reaches acertain desired value; and thereafter, dissolving the outer metal tubealone or together with the coated metal by a chemical method, andseparating them from the core filaments, thereby obtaining fine metallicfilaments.

According to this prior art method, the outer metal tube (A) alone ortogether with the coated metal (B) should be dissolved by dipping orelectrolysis using a specially selected reagent solution which does notreact with the fine metallic filaments present inside the tube, butreacts only with (A) or with (A) and (B) (A and B may be the same kindof metal). This dissolving operation generally takes a long time andrequires strict control of the conditions. Furthermore, because of usinga special chemical solution, the cost of production increases, and therecovery of the dissolved metal is difficult.

Accordingly, an object of this invention is to provide apparatus forproducing fine metallic filaments by the bundle drawing method whereinthe separation of the outer metal tube of the drawn composite wire iseffected by a mechanical procedure instead of the conventional chemicalprocedure, whereby the abovementioned defects of the prior art can beremoved, and the separation treatment of the fine metallic filaments ofthe composite wire can be performed by a simple apparatus within ashorter time, which reduces the cost of production, and whereby therecovery of the outer tube metal can be simultaneously performed insitu.

Another object of this invention is to provide apparatus for producingfine metallic filaments wherein by the mechanical procedure used for theseparation treatment instead of the chemical procedure, the finemetallic filaments do not undergo corrosion, and products of goodquality without breakage or deterioration in properties can be obtained.

SUMMARY OF THE INVENTION According to this invention, there is providedapparatus for producingfine metallic filaments by the bundle drawingmethod, wherein in order to separate the outer tube metal of the finaldrawn composite wire from the core filaments therein, the outer tubemetal on both sides of the composite wire is cut near to the corefilaments, and then both uncut surfaces of the composite wire arelightly rolled thereby to divide the composite wire continuously andthus form fine metal- Iic filaments.

The apparatus of the present invention for producing fine metallicfilaments comprises:

supply means for supplying a drawn composite wire comprising a bundle ofa plurality of metal filaments surrounded by an outer metal tube,

cutting means comprising cutting bites arranged symmetrically inrelation to said composite wire in said cutting means for cutting andremoving most of said outer metal tube of said composite wire onopposite sides of said metal tube,

rolling means comprising oppositely disposed rolls for pressing theuncut sides of said composite wire, causing said composite wire to becompressed and to spread outwardly in a direction perpendicular to saidcut sides of said metal tube and said metal tube to divide at said outsurfaces, and

take-up means for taking up the divided parts of said metal tube andsaid metallic filaments.

The above and other objects of this invention along with the featuresand advantages thereof will become fully apparent as the descriptionproceeds with reference to the accompanying drawings. Some embodimentsof the present invention are illustrated in the drawings, but theinvention is in no way limited thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1, 2, 3 and 4 show one exampleof the process of producing fine metallic filaments in accordance withthis invention, FIG. 1 showing a composite wire before drawing, FIG. 2the composite wire after drawing, FIG. 3 the composite wire aftercutting of both sides of the outer tube, and FIG. 4 fine metallicfilaments finally obtained.

FIG. 5 is a schematic view of an apparatus to be used for theperformance of the present invention to separate the outer tube metal ofthe drawn composite wire from the core filaments therein; and

FIG. 6 is a sectional view showing the state of cutting the outer tubemetal in the apparatus shown in FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with thisinvention, as shown in FIG.

1 same as in the above-described conventional method, a separator 2 iscoated on the surfaces of material wires 1, or a different metal 2 iscoated thereon by, for example, plating. A bundle of a plurality of thecoated material wires is inserted in a tube 3 of a different metal, orthe bundle of the material wires is covered with a metallic tape 3 atits outer circumference, followed by welding the seam portion to form acomposite wire 4. The separator or metal coated layer 2 on the surfacesof the material wires is not altogether necessary when the materialwires are not heat-treated in any subsequent step. Then, the compositewire obtained is subjected to a diameter reduction treatment by drawing,heat-treatment, etc. until the diameter of each core metallic wire 1reaches a desired value, and a composite wire having the section asshown in FIG. 2 is obtained. The drawn composite wire is subsequentlyprocessed by an apparatus of the type shown in FIG. 5. Referring to FIG.5, the reference numeral 4 represents a drawn composite wire including,for example, 91 high carbon steel filaments with a diameter of 0.050 mmand a mild steel tube having a thickness of 35 to 40 micrometerscovering the outer circumference of a bundle of the steel filaments. Asupply reel for the composite wire 4 is shown at 5. The composite wire 4is passed through an outer tube cutting device 6, and drawn out. Thedrawing force is imparted by rolls 8 or a capstan (not shown) disposedbetween 6 and 7. This device 6 consists of two cutting bites 14 arrangedsymmetrically to each other as shown in FIG. 6, and is adapted to cutthe outer metal 3 on both sides of the composite wire near to corefilaments 1 inside the outer tube so that the composite wire has asection as shown in FIG. 3. The outer tube metal is cut to an extent asclose as possible to the core filaments but without exposing thefilaments even at points 3 which are the deepest cuts. For example, whenthe thickness of the composite wire between the cut surfaces is 0.48 mm,a layer of the outer metal tube having a thickness of 0.010 to 0.015 mmremains.

The composite wire 4 in which the outer layer on both sides have beencut is rolled by rolls 8 slightly to press the upper and lower uncutsurfaces. At this time, it is necessary to provide a guide 7 whichprevents the composite wire 4' from tumbling down towards the entry sideof rolls 8.

By this rolling, the composite wire is collapsed upwards and downwards,and tends to spread laterally and become a flat wire. Since the surfacesof the core filaments have previously been coated with a separator suchas metal oxides, graphite or metal soap, the filaments slip over eachother, and are not deformed plastically. Hence, this stress inducing thelateral spreading to form a flat wire is concentrated on the thinnestpoints 3" of the outer metal as shown in FIG. 3, and these points arebroken. Thus, by the rolling operation, the outer tube metal is dividedinto the upper and lower portions 3' and 3 and is separated from thecore filaments 1. If the rolling force at this time is excessive, thecore filaments are plastically deformed to collapse. If, on the otherhand, the rolling force is small, the continuous break of the outer tubemetal does not occur.

Therefore, the rolling conditions should be determined optionally byexperiments in relation to the cutting conditions in the previous step.

The two divided outer metal portions 3 and a filament yarn 1' areseparated by separating guide rolls 9 into a yarn of fine metallicfilaments l and two outer metal portions 3', and coiled up by take-upreels ll, 12 and 13. The yarn of fine metallic filaments 1' thus takenup is in the state of being completely separated into the individualfilaments as shown in FIG. 4. This is due to the effect of the separatorpre-coated on the surfaces of the material wires.

A take-up device 10 having the take-up rolls 1], l2 and 13, for example,is of a slip-type take-up mechanism, or of a mechanism using a fixedtorque motor, whereby the yarn and outer metals are coiled up insynchronous relationship with the speed of rolling while a certainprescribed tension is being imparted to the yarn and outer metal.

The above-described apparatus and method makes it possible to remove theouter tube metal from the composite wire containing fine metallicfilaments therein by cutting and rolling and thus obtain a yarn of finemetallic filaments.

Since according to the present invention the separation treatment offine metallic filaments in the bundle drawing method can be performed bya mechanical procedure using a simple apparatus without carrying out atroublesome and expensive chemical or electrochemical treatment, theoperation is simple and the treatment time is short. Furthermore,because no cost is necessary for chemicals, the method has the advantagethat the cost of production becomes lower. In the conventional method,the outer tube metal is dissolved in a chemical as a result of thechemical or electrochemical treatment, the recovery of themetal must beeffected, for example, by electrolytic deposition or precipitation basedon the formation of hydroxides, and therefore, generally becomesdifficult and expensive. By contrast, in the present invention, it canbe recovered as metal quite simply. Hence, when an especially expensivemetal such as copper or nickel is used as the outer tube metal, the costof production can be greatly curtailed.

The invention will now be illustrated further by the following examples.

EXAMPLE 1 became 0.035 to 0.040 mm. Subsequently, the wire was Islightly rolled by six high rolls in which the diameter of the workingroll was 30 mm, and the outer tube metal was divided into two portions.These divided portions and a yarn of the fine metallic filaments thereinwere separately taken up. .A yarn of 91 fine metallic filaments with adiameter of 0.05 mm was continuously obtained at a speed of m/min.

EXAMPLE 2 Final Composite wire Outer tube metal: mild steel Finalfilament: 304 type stainless steel Diameter of the composite wire: 0.71mm Diameter of each filament (average): 0.035 mm Number of filaments:300 Thickness of the tube (average): 0.050 mm Separator on the filamentsurface: talcum powder The composite wire shown above was cut by thesame apparatus and method as used in Example l'except that the cutmargin was 0.020 to 0.025 mm. The subsequent procedure was the same asin Example 1, and a yarn of 300 fine metallic filaments having adiameter of 0.035 mm was obtained at a speed of 100 m/min.

We claim: 1. An apparatus for producing fine metallic filamentscomprising supply means for supplying a drawn composite wire comprisinga bundle of a plurality of metallic filaments surrounded by an outermetal tube, cutting means comprising cutting bites arrangedsymmetrically in relation to said composite wire in said cutting meansfor cutting and removing most of said outer metal tube of said compositewire on opposite sides of said metal tube, rolling means comprisingoppositely disposed rolls for pressing the uncut sides of said compositewire, causing said composite wire to be compressed and to spreadoutwardly in a direction perpendicular to said cut sides of said metaltube and said metal tube to divide at said cut surfaces, and

take-up means for taking up the divided parts of said metal tube andsaid metallic filaments.

2. The apparatus of claim 1, comprising additionally friction rolls or adrive-type capstan disposed between said rolling means and said cuttingmeans, around which said composite wire is wrapped a few turns fordrawing said composite wire through said cutting means.

3. The apparatus of claim 1, wherein a tumblepreventing guide isdisposed at the entry side of said rolling means, said guide beingadapted to press the cut surface of the composite wire lightly so as toposition the cut surface of said composite wire always at right anglesto the surfaces of the rolls upon entry of the composite wire betweenthe rolls.

4. The apparatus of claim 1, wherein said take-up means for the dividedportions of the outer tube metal and the metallic filaments comprises aslip mechanism or a fixed torque motor in synchronous relation to thespeed of said composite wire passing said rolling means, said compositewire being under a certain prescribed tension.

1. An apparatus for producing fine metallic filaments comprising supplymeans for supplying a drawn composite wire comprising a bundle of aplurality of metallic filaments surrounded by an outer metal tube,cutting means comprising cutting bites arranged symmetrically inrelation to said composite wire in said cutting means for cutting andremoving most of said outer metal tube of said composite wire onopposite sides of said metal tube, rolling means comprising oppositelydisposed rolls for pressing the uncut sides of said composite wire,causing said composite wire to be compressed and to spread outwardly ina direction perpendicular to said cut sides of said metal tube and saidmetal tuBe to divide at said cut surfaces, and take-up means for takingup the divided parts of said metal tube and said metallic filaments. 2.The apparatus of claim 1, comprising additionally friction rolls or adrive-type capstan disposed between said rolling means and said cuttingmeans, around which said composite wire is wrapped a few turns fordrawing said composite wire through said cutting means.
 3. The apparatusof claim 1, wherein a tumble-preventing guide is disposed at the entryside of said rolling means, said guide being adapted to press the cutsurface of the composite wire lightly so as to position the cut surfaceof said composite wire always at right angles to the surfaces of therolls upon entry of the composite wire between the rolls.
 4. Theapparatus of claim 1, wherein said take-up means for the dividedportions of the outer tube metal and the metallic filaments comprises aslip mechanism or a fixed torque motor in synchronous relation to thespeed of said composite wire passing said rolling means, said compositewire being under a certain prescribed tension.